94 A REVISION OF THE ASTACIDA. 
Neither of these forms has been reported from Pennsylvania or Virginia. 
The only species known to me to be common to the three States of New 
York, Pennsylvania, and Virginia are C. Blandingi, affius, and Barton’. Ra- 
finesque’s description fits none of them. Girard surmised, from the habits 
of C. fossor, that it might prove to be C. Diogenes. 
In the collections of the Boston Society of Natural History and the 
Museum of Comparative Zodlogy (Cat. No. 3590) there are three second- 
form males of a Cambarus which closely resemble C. propinguus, but the 
sexual appendages are longer, as in C. rusticus. The epistoma is long. The 
carpus has a strong internal median carpal spine and a small basal internal 
spine; beneath, the carpus is unarmed. The biserial spines of the meros 
are well developed. The outer ramus of the first abdominal appendages is 
a little recurved at the tip. The largest of these specimens is 75 mm. long. 
No locality is given. They seem to belong to an undescribed species. 
389. Cambarus Harrisonii. 
Plate Ill. fig. 1, Plate IX. figs. 9, 9. 
Cambarus Harrisonii, Faxon, Proc. Amer. Acad. Arts and Sci., XX. 130, 1884. 
Male, form I.— Rostrum long, narrow, deflexed, excavated; margins 
thickened, a little convergent; acumen of moderate length, triangular, 
acute ; marginal spines short, obtuse, often obsolescent. Carapace flattened 
above, coarsely punctate, granulate on the sides; post-orbital ridges prom: 
inent, suleate without, with acute anterior spine; antero-lateral margin 
notched at base of antenna; cervical suture not sinuate, interrupted on the 
side; lateral spine small, acute; branchiostegian spine obsolete; areola at 
least one half as long as the distance from the tip of the rostrum to the 
cervical groove, of moderate width, punctate, the dots tending to a biserial 
arrangement in the middle portion. Abdomen as long as the cephalothorax ; 
telson long, posterior margin rounded, posterior margin of basal segment 
bispinous on each side. Basal segment of antennule with an internal, sub- 
apical, inferior spine. Antenne as long as the body; second segment armed 
with a short, acute, external spine; scale as long as the rostrum, of moderate 
width, widest near the middle, thence tapering to the acute external apical 
spine. Anterior process of epistoma with convex sides, apex blunt or trun- 
cate. Third pair of maxillipeds hairy within. Chelipeds of moderate length, 
thick ; chela large, broad, coarsely punctate above and below, inner margin 
